The International Information Center for Geotechnical Engineers
Our Sponsors
Advertising
Advertising
Geomap
Apps

HOME
NEWS
EVENTS
PUBLICATIONS
EDUCATION
JOBS
SOFTWARE
MEDIA
GEOMAP
ADVERTISING
OUR SPONSORS

Rocscience Inc.'s Technical Workshop: Slope Stability Analysis with Limit Equilibrium (Slide2) and Finite Element (RS2) begins on Oct 14th 2026

Home
Education
Soil Mechanics
Angle of Internal Friction

Rocscience Inc.'s Technical Workshop: Slope Stability Analysis with Limit Equilibrium (Slide2) and Finite Element (RS2) begins on Oct 14th 2026

Create a free account and view content that fits your specific interests in geotechnical engineering Learn More

Angle of Internal Friction

Soil Mechanics

Contents [hide show]

Description
Web Class Assignments

The angle of internal friction (φ) is the measure of the shear resistance of soil due to particle interlocking and frictional resistance between soil grains. It represents the slope of the shear strength envelope with respect to the normal effective stress axis in the Mohr–Coulomb failure criterion.

Typical ranges are:

Loose sand: 28-30°
Dense sand/gravel: 35-45°
Silts: 25-35°
Clays: often 0-20° (when considering drained vs. undrained conditions)

A quick estimate, but less precise, of internal friction angle φ, can be derived from direct shear test. For a more accurate estimation, used for design purposes, triaxial shear test is preferred. When laboratory tests are not available, field correlation methods can be used for preliminary design purposes.

Want to read more like this?

Shear Strength of Soils

May, 13, 2019 | Education

Shear strength is defined as the maximum shear stress that the soil may sustain without experienci...

Simple Shear Test

Sep, 11, 2024 | Education

Introduction The simple shear test, as the name suggests, is a method used to define a...

Direct Shear Test

May, 28, 2020 | Education

Introduction The Direct Shear Test is an experimental procedure conducted in geotechnical engi...

VertekCPT: Do you know about Soil Shear Strength ?

Jun, 24, 2015 | News

Shear strength is the ability of a material to resist shear forces - that is, forces that produce a...

CPT Interpretation: Soil Parameters φ’, E, Vs, M

Oct, 25, 2024 | Education

Acknowledgement: This page has been reproduced from P. K. Robertson, K.Cabal, Guide to Cone Pene...

SHEAR Version 4

Jun, 15, 2023 | Software

Laboratory Testing

Apr, 21, 2020 | Education

Laboratory testing is an integral part of geotechnical engineering research and practice. A well...

SO-Shear

Jun, 15, 2023 | Software

GEO5 Laboratory

Jan, 12, 2024 | Software

Web Class Assignments

The tilt of the Leaning Tower of Pisa: Why and How?

CE 179-Geosystems Engineering Design

The Leaning Tower of Pisa is one of the most famous constructions in the world. Its fame not only comes from the original trigger for its construction – to show the importance of this city after...

Land Subsidence and Monitoring in Indonesia

CE 179-Geosystems Engineering Design

Hello, and welcome to my project report for CE179! My name is Victoria Lim, and I am a current senior at UC Berkeley, studying Civil and Environmental Engineering. In this report, I hope that you wi...

An introduction of Micropiles on expansive and karst ground conditions through the design lens of bearing capacity

CE 179-Geosystems Engineering Design

The history of micropiles stems over seven decades ago from Europe though widespread acceptance and standardization of the technology is more recent and has not matured for as long as its first docu...

Helical Piles

CE 179-Geosystems Engineering Design

Helical piles are a form of prefabricated deep foundation. As hinted in its name, helical piles differ from other deep foundations and are most notable for having spiraling blades along their shafts...